What section 75 actually says
The section is headed "Power to prevent damage and to take steps to prevent contamination, waste etc." It bites where a water undertaker has reason for believing one of four things about premises it supplies. The fourth, at section 75(1)(d), is the one that covers leaks: that water supplied "is being or is likely to be wasted or, having regard to the purposes for which it is supplied, misused or unduly consumed".
Once that belief exists, section 75(2) gives them a choice of two powers. In an emergency, under 75(2)(a), they may disconnect the service pipe or otherwise cut off the supply. In any other case, under 75(2)(b), they may serve notice on the consumer "requiring him to take such steps as may be specified in the notice as necessary to secure that the damage, contamination, waste, misuse or undue consumption ceases or, as the case may be, does not occur".
Thames Water's household customer side leakage code of practice sets out the same thing in their own words: if they have reason for believing water supplied to your property is being or is likely to be wasted, they have the power under section 75(2)(b) to serve you with a notice requiring the necessary repairs by a specified date.
The deadline, which is two different numbers
This is where people get confused, so take them separately.
| Number | Where it comes from | What it means |
|---|
| Seven days | Section 75(6)(a), Water Industry Act 1991 | The statutory floor. A notice must specify a period "not being less than the period of seven days beginning with the day after the service of the notice". |
| Four weeks | Thames Water's published policy | What Thames Water actually give you. "Whether you find a leak or we confirm one at your property, you must fix it within four weeks." |
So the four weeks is not in the Act, and the seven days is not Thames Water's normal practice. The statutory minimum matters because the date on the notice is the date that counts in law, not the policy. Read the notice and work to the date printed on it.
Note also when the clock starts. Thames Water's code of practice puts it as four weeks "of us confirming it" — confirmation, not the day you first suspected something. Their leaks page phrases it as four weeks whether you found it or they reported it to you.
What the notice must contain
Section 75(6) sets two requirements. The notice must specify the period within which the steps are to be taken, subject to the seven-day floor. And it must set out the undertaker's powers under subsections (7) to (9).
That second requirement is a practical check. A notice that does not tell you what happens next is not a notice that complies with section 75(6)(b). If what arrived is a letter saying you have a leak and asking you to fix it, that is a letter, not necessarily a formal notice under the section, and it is worth establishing which you are holding before you make decisions on it. Thames Water's own code distinguishes the two by heading the formal version a waste of water notice.
What happens if you miss the date
Three different things can follow, depending on the circumstances.
They do the work and bill you
Section 75(9) is the main route. Where the steps in the notice have not been taken by the end of the period specified, the undertaker has power to take those steps itself, and to recover any expenses reasonably incurred in doing so from the person on whom the notice was served. Thames Water describe this as an enforced repair, and say they will "arrange for the repair works to be undertaken by our contractors and recover all costs from you including our administration charges".
Two words in the statute are worth holding on to: reasonably incurred. Section 75(9)(b) limits recovery to expenses reasonably incurred, not to whatever the invoice says.
They disconnect
Section 75(7) allows disconnection or cut-off in two situations only: where the case becomes an emergency, or where "the premises appear to be unoccupied and the steps specified in the notice are not taken before the end of the period so specified". Thames Water mirror both, describing cut-off where there is a serious risk of flooding or to public health, and possible disconnection where the property appears unoccupied and no repair work has taken place. Where they do cut off, section 75(3) requires them to serve a notice as soon as reasonably practicable specifying the steps you must take before the supply is restored, and section 75(5) makes failing to serve that notice, without reasonable excuse, an offence punishable by a fine not exceeding level 3 on the standard scale.
An occupied house with an ordinary supply pipe leak is not in scope for disconnection under 75(7) on the strength of a missed date alone.
They come to the door, and you do not open it
Thames Water's code of practice says that if you refuse them entry when they attempt to carry out the enforced repair, they may charge you for the wasted visit, and if you continue to refuse access they may apply to the magistrates' court for a right of entry warrant to access the property and repair the leak.
The protection in subsection (10)
Section 75(10) is short and useful. Where steps are taken under the section and it is shown that, in the circumstances, those steps were not necessary, the undertaker is not entitled to recover any expenses it incurred, and must pay any other person who took those steps an amount equal to their reasonable expenses.
In plain terms: if the leak was not on your side, or there was no leak, the bill does not stand and somebody else's costs may be recoverable. Which is the practical argument for establishing where the water is going before the four weeks run out, rather than after an enforced repair has been carried out and invoiced.
Section 75 is not the offence
Worth separating, because the two get mixed together. Section 75 is a power to make the waste stop. Section 73 is the offence: an owner or occupier who intentionally or negligently causes or allows a fitting they are responsible for to waste water commits an offence punishable by a fine not exceeding level 3 on the standard scale, subject to the approved contractor defence in section 73(1A). Receiving a section 75 notice is not a conviction and is not a criminal charge. It is an instruction with a date on it.
What to do with the four weeks
- Confirm the leak is real and is yours. With a meter: turn off the internal stop valve, take a reading, wait half an hour with nothing drawing water, read again. A rise means water is moving on the supply pipe between the meter and that valve. Thames Water publish the same test.
- Establish which pipe. Water surfacing in the road or pavement is theirs. Water inside your boundary is almost certainly yours. Where the boundary falls is a page of its own because it is not obvious.
- Get it located before anybody digs. An excavation in the wrong place costs the dig and the reinstatement and finds nothing.
- Keep the paperwork. A certificate of water regulations compliance from the plumber, and the invoice. Thames Water ask for proof of repair, and it is also the evidence that the date was met.
- Tell them it is fixed. They ask you to confirm so they can record that the problem was resolved within four weeks.
If the repair genuinely cannot be completed in the window — a shared supply where a neighbour will not engage, a pipe running under a vault, access that needs a permit — say so in writing before the date passes rather than after. A documented reason and a booked date is a different conversation from silence.
When not to call us
If the notice concerns a dripping tap, a running overflow or a leaking loo, fix it yourself or call any plumber; that is not a detection job and paying detection rates for it would be silly. If you rent, the repair is your landlord's and your job is to put it to them in writing and keep the copy. If you are disputing the bill from an enforced repair rather than needing a leak found, that is a complaint to Thames Water and then to CCW, not a job for an engineer.
Where we are useful is the middle case: the notice is real, the leak is inside your boundary, nobody knows where it is, and the clock is running. We work at £150 per hour agreed in advance, and if we do not find the leak you do not pay for the time we spent looking. Supply pipe work and the making good afterwards are the same visit, not two firms.
